System selection is one of the first tasks a device must perform upon power-up. Its implementation impacts how long a user must wait before attaching to a network to make a voice or a data call. Therefore the operators must make sure that this process is seamless from a user's perspective. With most of the operators migrating from the existing 2G/3G to 4G networks, it becomes challenging to verify the multimode system selection capability of the mobile device.
The mobile devices that belong to 3GPP technologies like GSM/GPRS/WCDMA/HSPA use a PLMN based system selection whereas the 3GPP2 based mobile devices that belong to CDMA 2000/EV-DO use a PRL/ePRL based system selection. With 4G LTE coming into picture the operators need to have a seamless migration plan in supporting these technologies without user interruption.
A UICC may contain several applications, making it possible for the same smart card to give access to both 3GPP and non-3GPP networks. 3GPP has approved some important features in the USIM to enable efficient network selection mechanisms. With the addition of CDMA2000 and HRPD access technologies into the PLMN, the USIM PLMN lists now enable roaming selection among CDMA, UMTS, and LTE access systems. Taking advantage of the standards, USIM now stores mobility management parameters for SAE/LTE.
The UICC cards must be capable of supporting multimode technologies for a seamless system selection. Therefore the devices with these capabilities need to be tested in the lab before they are commercially released into the market. And testing these devices by providing typical scenarios would take a long time if done manually.
Currently the mobile devices that belong to CDMA 2000/EVDO networks require Preferred Roaming List (PRL) to acquire the right system. Whereas the mobile devices that belong to GSM/UMTS/LTE networks use PLMN list to acquire the right system.
When a mobile device supports multi-mode capability that works across all standards the device needs a better system selection process to choose the right network. The MMSS related information like MLPL, MSPL, PRL/ePRL and PLMN identities combined together provides the device all the relevant information for it to decide which would be the right system for it to acquire. It is clear that a device's ability to acquire the proper system is paramount not only for user satisfaction, but also for the carrier to provide the most cost effective service. Thus, proper testing of system acquisition and section of the PLMN & ePRL order is of utmost importance.